Thermal degradation and flame retardancy properties of ABS/lignin: Effects of lignin content and reactive compatibilization

• Published in: Thermochimica acta Vol. 518; no. 1; pp. 59 - 65
• Main Authors: Song, Pingan, Cao, Zhenhu, Fu, Shenyuan, Fang, Zhengping, Wu, Qian, Ye, Jiewang
• Format: Journal Article
• Language: English; Dutch
• Published: Oxford Elsevier B.V 10.05.2011; Elsevier
• Subjects: ABS; ABS resins; Applied sciences; calorimeters; Combustion; Compatibility; Compounding ingredients; Degradation; Exact sciences and technology; Fireproof agents; Flammability; heat; Heat release rate; Lignin; Lignin and derivatives; Natural polymers; Physicochemistry of polymers; Polymer industry, paints, wood; Reactive compatibilization; Reduction; Residues; Technology of polymers; thermal analysis; thermal degradation; Thermal stability; Degradation; Flammability; Lignin; ABS; Reactive compatibilization; Scanning electron microscopy; Pyrolysis; Flame retardant; Surface structure; Morphology; Thermal analysis; Copolymer; Compatibility; Thermal degradation
• ISSN: 0040-6031; 1872-762X
• DOI: 10.1016/j.tca.2011.02.007

[Display omitted] ► Lignin can slow the degradation process and increase the char residue of ABS. ► Addition of 20% lignin into ABS can reduce the peak heat release rate by ∼32%. ► Reactive compatibilization can further decrease the flammability of ABS resin. ► Better dispersion of lignin results in the much more intact char layer. ► The better barrier effects are responsible of the improved flame retardancy. Effects of alkali lignin incorporation and in situ reactive compatibilization on the thermal stability and flame retardancy of ABS were investigated. Morphology observations show that lignin can form submicron dispersed phases in ABS matrix regardless of compatibilization. Thermal analyses show that lignin will cause a slight thermal instability of ABS due to its relatively lower thermal stability, and compatibilization reaction has little effluence on that. However, lignin can slow the degradation process and increase the char residue of ABS with increasing lignin loading, and the compatibilization does not markedly affect them. Cone calorimeter tests demonstrate that lignin can significantly reduce the heat release rate, and slow the combustion process of ABS, e.g., 20 wt% lignin causing a 32% reduction in peak heat release rate (PHRR). The compatibilization can further reduce the flammability of ABS due to the improved char layer. The char residue analyses indicate that the formation of protective char layer of lignin is primarily responsible for the enhanced flame retardancy.